The invention relates to a mobile coater apparatus for coating a surface with an ultraviolet or electron beam curable coating.
Various types of coatings are applied to surfaces in order to protect the surfaces from corrosion or to provide a surface having a particular desirable characteristic or property. Many of the coatings are applied by conventional methods, such as spraying, dipping or rolling the coatings onto the surface. Water-based or oil-based coatings applied by these methods are typically air dried or heat dried either by convective heat, radiant heat or microwave energy and the like.
Coatings which require more elaborate methods of curing such as ultraviolet or electron beam curing methods are typically conducted by placing the coated materials in a stationary curing device. This method works well for object which are small enough to fit into the curing device. For extremely large objects or surfaces too large or cumbersome to transport or move through such devices, alternate coating materials which may be less effective than ultraviolet or electron beam curable coatings are often required to be used.
There is a need therefore for a coater apparatus and method for coating large surfaces which cannot be easily transported through stationary curing devices and/or otherwise avoids the limitations of stationary curing devices.
With regard to the above and other objects and advantages therefore the invention provides a coater apparatus which includes a housing providing a curing energy source shield and having at least one first compartment and at least one second compartment. A partition wall between the first compartment and the second compartment separates the first compartment from the second compartment. A coater selected from spray and roll coaters is disposed in the first compartment. The second compartment includes a curing energy source selected from ultraviolet and electron beam energy sources. The coater apparatus also includes means for moving the housing across the surface during a coating operation and for maintaining a gap between the housing and the surface to be coated. Means is also included for controlling the coater and energy source during a coating and curing operation.
In another aspect the invention a coater apparatus including a first discrete compartment having a coater therein selected from spray and roll coaters and a second discrete compartment adjacent the first compartment and having therein a curing energy source selected from ultraviolet and electron beam energy sources. The first and second compartments are configured for receiving a work piece therein and the coater apparatus includes means operatively associated with the first and second compartments for maintaining a gap between the work piece and the coater and for moving the coater apparatus in a predetermined direction at a predetermined rate relative to the work piece for applying a coating composition to the work piece and for subsequently curing of the applied coating composition by the energy source.
An important advantage of the invention is that it provides an apparatus and method which may be adapted to coat and cure large surfaces with electron beam or ultraviolet curable materials. In contrast to conventional coating materials, electron beam or ultraviolet curable materials can typically be cured in a matter of seconds as opposed to hours. Another advantage of the invention is that the housing is adapted to limit escape of the coating materials to the environment during the coating step thereby generating little or no environmental emissions and significantly reducing worker exposure to such materials. The apparatus is also adaptable to sufficiently protect personnel from the curing energy source during curing operations for the coating.